Check Engine Light Guesses??!?!?

Hey Guys,

In the past 3 months my check engine light has popped on a few times I believe it is a misfire tripping the light but Im not completely sure. I plan to replace my spark plugs because they need it badly. BUT I wanted to see if you guys thought they may be my cause for the check engine light coming on. I unplug my battery for a few minutes and the light goes off and stays off for about a month or so and than it will come on when I am driving at random.

Since it stays off and comes back every so often do you this is a misfire and can be fixed by spark plug replacement? Any advice would be appreciated!

 

Next time, bring it to Autozone or Advance Auto. They'll scan the code for free. This will prevent you from wasting your time and money just throwing parts at it.

It could be a misfire, sure. Could be a busted gas cap. Could be timing. Could be anything. Only way to know for sure is pull the code next time.

I myself have an Ultragauge, that will read the code for me if my light comes on.

 

I did go to autozone and I got told that they have a new restriction placed on them by the state and they no longer do scans. called toyota they want $90.00 to do it. I am thinking Ill maybe run over to a local auto shop and see if theyll scan it for me. I am definitely over my guess diagnostic.

 

I had something very similar going on with my truck about a year ago. The light would come on then go off randomly. I ended up taking it to a shop, they pulled a code (don't remember what it was) and there was a long list possible problems. The first thing they did was clean the maf sensor and reset the light. To this day it has not come back on.

 

pickup an odbii adapter and torque for android. No sense in guessing.. You won't get anywhere without codes..

 

Yup.

ACSC lobbied and Suckramento passed a law that if a parts store does not have a service bay, they can not diagnose problems or touch a customer's vehicle.
Honestly, I see their point... a minimum wage employee can not properly diagnose a vehicle from reading a code. Just because you have an O2 sensor code does not mean that the O2 sensor is bad... it might be doing its job and giving a perfectly valid code.

But Autozone CAN allow you to BORROW a code reader. Pull the code and post it up. Someone here will be able to point you in the right direction, but we can't help without knowing the Pxxxxx code.

 

Yea, just borrow theirs. Pretty simple process.

Walk in and ask for the code reader, (sometimes you have to give them your ID), then just plug into port. It'll give you step by step directions, then list the code number. Write code down, then post up here.

Do this before you start throwing money at parts.

 

My experience is that o2 sensors get weak/lazy and it sets a code. Then it goes away by itself. If I pull a battery cable it'll go away for afew weeks, but always come back. This happened on my 02 tacoma, 00 sienna and 07 highlander. Right about 65000 miles on each; two front 02 sensors on the sienna (3.0l v6), front on the 02 (2.4l) and just had the rear o2 replaced on the highlander (~$500 for each).

 

I'd say this might be a good excuse to buy an Ultragauge, or see if someone in your area has one or a Scangauge. Worst case the UG is about $60 new and this one time will pay for itself versus the $90 you mentioned earlier.

Thanks for the clarification on the Autozone thing, I wasn't aware of that change. Kind of makes sense..just stupid that the legislature is too blind to see that the tool, not the person, is doing the work in this case.

 

it is likely the MAF needs cleaning if you can clear it and it stays clear for a little while

misfires make it blink during the misfire events and store a code as well

cheap code readers on fleabay for like 25 bucks, nice to have

 

True, I prefer the UG since I use it to monitor my driving habits. Figure if I save a gallon per fillup (which I have done minimally), it pays for itself in 3 months.

Plus it saved me having to run to the store with my wife's rig when it gave me the light.

 

Looks like a tripped a P0430 code (cat converter) so I gotta get under the truck check out my wiring and sensor make sure those are good and if they are than look into my options on replacing the unit.

 

Could use more info about your truck, like year, engine, mileage, etc. You may have a blown out cat, or lots of other issues.

 

if thats their excuse... buy a scanner, go out to the parking lot scan for codes and return the scanner 3 minutes later.

 

Truck is an 2005 access cab V6 Prerunner with 165,000 miles on it. There is a likely chance its a blown cat.

 

I coulda just looked at your pic... sorry im so damn lazy. Nice looking truck BTW.

 

Catalytic converters are wear items, and with 165K, it may be time for a new one. Only problem is if you're in CA, you have to buy an OEM cat. Can't buy aftermarket!

 

Scanners are relatively cheap these days. Just buy one. You'll use it again and again!....

 

There are CA-approved aftermarket cats, but they cost $200 more than what they would in AZ.

 

Or buy the Ultragauge, for the $60 or so it's not much more than a cheap scanner and you'll get the use out of it